Vacuum cleaner

ABSTRACT

A vacuum cleaner comprising a main body and a separating apparatus associated with the main body, wherein the main body includes a suction generator for drawing air into the separating apparatus and a handle arrangement including a trigger member for activating the suction generator. The trigger member is resiliently biased into a first position in which the suction generator does not operate, and is movable into a second position to activate the suction generator, wherein, when in the first position, a contact surface of the trigger member is spaced away from an adjacent surface of the handle arrangement and, when in the activated position, the contact face of the trigger member is substantially flush with the adjacent surface of the handle arrangement. The invention also relates for a handle arrangement for such a vacuum cleaner.

REFERENCE TO RELATED APPLICATIONS

This application claims the priority of United Kingdom Application No.1202349.5, filed Feb. 10, 2012, the entire contents of which areincorporated herein by reference.

FIELD OF THE INVENTION

The invention relates to a vacuum cleaner.

BACKGROUND OF THE INVENTION

There are various types of vacuum cleaners available on the market, andthese can be categorized generally into “cylinder” vacuum cleaners,“upright” vacuum cleaners, “handheld” vacuum cleaners and “stick” vacuumcleaners, also known as “stick-vacs”.

Cylinder and upright vacuum cleaners are commonplace and are generallyused as a household's primary vacuum cleaner for heavy-duty cleaningtasks around the home. As a result they tend to be mains-operated. Incontrast to cylinder and upright vacuum cleaners, handheld vacuumcleaners are portable in the sense that they are light enough to becarried in the hand and do not need to be supported on the floor by arolling assembly like cylinder and upright vacuum cleaners. Typically,they are powered by batteries. Because of this, handheld vacuum cleanersare better suited to low-duty cleaning jobs such as spot-cleaning offloors and upholstery and vehicle interiors, for example.

Stick-vac cleaners are marketed as offering a lightweight alternative toupright cleaners for relatively low duty floor-cleaning applications,such as cleaning up floor spills.

Common with all types of vacuum cleaners is the requirement for a userto be able to turn them on and off. Typically, a simple on/off button isprovided that can be pressed to turn the machine off and then pressedagain to turn the machine off.

SUMMARY OF THE INVENTION

The invention relates to improvements in the means for activating anddeactivating vacuum cleaners.

The invention provides a vacuum cleaner comprising a main body and aseparating apparatus associated with the main body, wherein the mainbody includes a suction generator for drawing air into the separatingapparatus and a handle arrangement including a trigger member foractivating the suction generator. The trigger member is resilientlybiased into a first position in which the suction generator does notoperate, and is movable into a second position to activate the suctiongenerator, wherein, when in the first position, a contact surface of thetrigger member is spaced away from an adjacent surface of the handlearrangement and, when in the second position, the contact face of thetrigger member is substantially flush with the adjacent surface of thehandle arrangement.

Although the trigger member could be a sliding trigger, it is currentlypreferred that the trigger member is supported on a pivot in theinterior of the handle arrangement. A sliding trigger has a relativehigh friction interface with the handle since it must slide on rails sothe pivoting arrangement of the invention beneficially enables a lighteraction trigger. In the invention the substantially flush relationship ofthe contact surface with the adjoining portions of the handlearrangement provides a particularly ergonomic user interface. Duringextended periods of cleaning, the requirement to depress a ‘dead man'strigger’ arrangement in order to operate the vacuum cleaner may becometiresome, particularly as the user's finger must adopt a slightlyextended position to maintain pressure on a trigger surface that standsproud from the grip during operation. This will affect especially thoseusers with comparatively small and/or weak hands. In the invention,since the contact face in effect ‘merges’ with the handle when thetrigger is depressed, the user's grip is able to adopt a more naturalposition which ensures that it is less tiring to maintain the trigger inthe operating state for an extended period of time.

The trigger member may be biased into the first position by way of aspring element which exerts a predetermined activation force on thetrigger member and, in one embodiment, the spring element is acompression spring that acts on a part of the contact surface. Inaddition to the low profile character of the trigger member, to furtherimprove the ergonomics of the trigger member it is preferably biasedwith a force of less than 8 N (Newtons), and particularly between about0.5 N and 6 N. Still preferably, between about 0.5 N and 3 N whichensures an easy action to the trigger.

The trigger member may include an actuating member that is moved bymovement of the contact face, the actuating member being arranged tocontact an activating switch of a battery pack which is, preferably,carried adjacent an end of the handle arrangement and may include a partwhich extends inside the interior of the handle, the extending partincluding the activating switch.

The vacuum cleaner of the invention may include an electronic controlmodule that is interfaced to the battery pack, the motor and fan unitand, in one embodiment, the trigger member and is operable to activatethe motor and fan unit in response to a command signal initiated by thetrigger member. Following receipt of the command signal, the controllermay implement a predetermined delay period before activating the motorand fan unit. Potentially the delay could be configured (duringmanufacture for example) for any period of time but it is preferred ifthe delay is a relatively short period for example less than one second.Preferably the delay period is between half a second (0.5 seconds) andone second. Beneficially, the delay period guards against momentaryoperation of the motor in the event that the user presses the switchaccidentally, for example by brushing the trigger lightly when graspingthe vacuum cleaner but before being ready to begin cleaning. Such afeature improves the user experience but also reduces wear on the motorby reducing the number of start/stop cycles significantly over thelifetime of the machine.

It is envisaged that the handle arrangement may be an integral part ofthe vacuum cleaner, although it may also be a removable part. Therefore,expressed another way the invention provides a handle arrangement for avacuum cleaner, the handle arrangement including a trigger member whichis movable between first and second positions, the trigger member beingresiliently biased into the first position in which position a contactsurface of the trigger member is spaced away from an adjacent surface ofthe handle arrangement and wherein, when in the second position, thecontact face of the trigger member is substantially flush with theadjacent surface of the handle arrangement.

In a second aspect, the invention provides a cylinder vacuum cleanercomprising a main body supportable on a surface by a rolling assembly,and a separating apparatus associated with the main body, wherein themain body includes a suction generator for drawing air into theseparating apparatus, wherein a flexible hose extends from the main bodyand the hose having a handle including a trigger member for activatingthe suction generator, the trigger member being resiliently biased intoa first position in which the suction generator does not operate, and ismovable into a second position to activate the suction generator.

In a third aspect, the invention provides an upright vacuum cleanercomprising a main body supportable on a surface by a rolling assembly,and a separating apparatus associated with the main body, wherein themain body includes a suction generator for drawing air into theseparating apparatus through an associated cleaning head, wherein themain body has a handle associated therewith, the handle including atrigger member for activating the suction generator, the trigger memberbeing resiliently biased into a first position in which the suctiongenerator does not operate, and is movable into a second position toactivate the suction generator.

Preferred and/or optional features of the first aspect of the inventionmay also be combined with the second and third aspects of the inventioneither alone or in combination.

BRIEF DESCRIPTION OF THE DRAWINGS

So that it may be more readily understood, embodiments of the inventionwill now be described by way of example only with reference to theaccompanying drawings, in which:

FIG. 1 is a perspective side view of a handheld vacuum cleaner inaccordance with the invention;

FIG. 2 is a side view of the vacuum cleaner in FIG. 1 with a section ofthe handle cut away;

FIG. 3 is a perspective side view of the handheld vacuum cleaner in FIG.1 but with the operating trigger/switch in a second position;

FIG. 4 is a side view of the vacuum cleaner, as in FIG. 2, but with theoperating trigger in the second operating position;

FIG. 5 a is a simplified section view through the handle showing theoperating trigger in the first operating position;

FIG. 5 b is a view of the handle like that in FIG. 5, but with theoperating trigger in the second operating position;

FIG. 6 is a schematic view of a control system of the vacuum cleaneraccording to the invention;

FIG. 7 is a flowchart of a control process implemented by the controlsystem;

FIG. 8 is a perspective view of an alternative embodiment of vacuumcleaner in accordance with the invention;

FIG. 9 is an enlarged side view of a handle arrangement of the vacuumcleaner in FIG. 8;

FIG. 10 is a view of the handle arrangement in FIG. 9 with a section cutaway to show its interior;

FIG. 11 is an enlarged view of the handle arrangement in FIG. 9 whereinthe trigger member is shown in a second operating position; and

FIG. 12 is a view of the handle arrangement in FIG. 11 with a sectioncut away to show its interior.

DETAILED DESCRIPTION OF THE INVENTION

Referring firstly to FIGS. 1 and 2, a handheld vacuum cleaner 2 has amain body 4 which houses a motor and fan unit, an outer housing of whichis indicated generally at 6. The motor and fan unit 6 is located above agenerally upright handle or grip portion 8. The lower end 8 a of thehandle 8 supports a generally slab-like battery pack 10. A set ofexhaust vents 12 are provided on the main body 4 for exhausting air fromthe handheld vacuum cleaner 2.

The main body 4 supports a cyclonic separating apparatus 14 thatfunctions to remove dirt, dust and other debris from a dirt-bearingairflow drawn into the vacuum cleaner by the motor and fan unit. Thecyclonic separating apparatus 14 is attached to a forward part 4 a ofthe main body 4 and an air inlet conduit/nozzle 16 extends along alongitudinal axis X-X from a forward portion of the cyclonic separatingapparatus 14 that is remote from the main body 4. The air inlet nozzle16 is configured so that a suitable brush tool can be mounted to it andincludes a catch 18 for securely holding such a brush tool when the toolis engaged with the inlet. The brush tool is not material to the presentinvention and so is not shown here. An elongate extension tube or wand(not shown) may also be mounted to the air inlet nozzle 16 to extend thecleaning reach of the vacuum cleaner.

The cyclonic separating apparatus 14 is located between the main body 4and the air inlet nozzle 16 and has a longitudinal axis Y-Y whichextends in a generally upright direction so that it is substantiallyorthogonal with the longitudinal axis X-X of the inlet nozzle 16. Thehandle 8 extends along an axis Z-Z that lies at a shallow angle to theaxis Y-Y and which, in the exemplary embodiment is approximately 10degrees, although any angle from orthogonal to about 20 degrees issuitable.

The handle 8 is oriented in a pistol-grip formation which is acomfortable interface for a user since it reduces stress on a user'swrist during cleaning. The cyclonic separating apparatus 14 ispositioned close to the handle 8 which also reduces the moment appliedto the user's wrist when the handheld vacuum cleaner 2 is in use. Thehandle 8 carries an on/off switch arrangement in the form of a triggermember 20 for turning the motor and fan unit 6 on and off. In use, themotor and fan unit draws dust laden air into the vacuum cleaner 2 viathe air inlet nozzle 16. Dirt and dust particles entrained within theair flow are separated from the air and retained in the cyclonicseparating apparatus 14. The cleaned air is ejected from the rear of thecyclonic separating apparatus 14 and conveyed by a short duct section 22to the motor and fan unit 6 located within the main body 4, and issubsequently expelled through the air outlets 12 which may also includea fine particle filter by way of a final filtering stage to removemicro-contaminants from the airflow that exits the cleaner.

It should be noted at this point that although the cyclonic separatingapparatus described here is cyclonic, this is not essential to theinvention and other separating apparatus are viable, for example otherbagless-type separating apparatus which feature a fibrous filter elementin a whirl-chamber to separate contaminants from the airstream, or evena bagged-type separating apparatus as is common in the art. The preciseconfiguration of the cyclonic separating apparatus is not material tothe present invention and so will not be described in detail here.However, one particular configuration of cyclonic separation that issuitable is described in the Applicant's co-pending applicationGB2475312A.

Turning now to FIG. 2, there is shown a side view of the handheld vacuumcleaner 2 in FIG. 1 but with a portion of the outer skin of the handlecutaway so the interior of the handle can be seen and, in particular,the on/off trigger arrangement.

The battery pack 10 has a generally rectangular block-like base portion23. An upstanding post 24 extends upwardly at an angle of approximately80° to the plane of the base portion 23. The handle 8 is tubular incross section with a generally oval shape that complements the crosssection of the post 24 of the battery 10. Therefore, the post 24 of thebattery 10 is receivable by the open lower end 8 a of the handle 8 sothat the battery pack 10 may be docked onto the vacuum cleaner 2. Anupper end of the post 24 includes electrical terminals (not shown) thatconnect to corresponding electrical connectors housed in the interior ofthe handle 8 and which lead to an electronic control module (not shown)that is interfaced to the motor and fan unit. Electrical power istherefore transmitted from the battery pack 10 to the motor and fan unit6 via the electrical connectors. The exact configuration of theelectrical battery terminals and their respective connectors are notessential to the invention so will not be described in more detail here.

The battery post 24 also includes a mechanically actuated switch unit 26that is oriented so as to extend upwardly from the top face of the post24. The switch unit 26 includes a push switch member 28 and is operatedby an end of the trigger member 20, as will now be described.

The trigger member 20 takes the form of a bell crank having a first end20 a in the form of an actuating finger that is engageable with thebattery switch unit 26 and a second end 20 b that provides a contactface for the trigger member 20 and which protrudes through a forwardlyfacing aperture 30 in the handle 8. The contact face 20 b of the triggeris seen clearly in FIG. 1 extending through the aperture 30. Aplate-like finger rest 32 extends forwardly from the handle 8 at aposition just below the aperture 30 and provides a means to prevent auser's finger from slipping off the trigger member 20 in use. It alsoallows a user to grasp the handle without actuating the trigger, duringcarrying for example.

The trigger member 20 is biased into a non-actuating position by aspring element 34 which, in this embodiment is a coil spring, thatextends between a spring retaining member 36 provided on the rear of thecontact face 20 b and a spring abutment member 38 provided in the handle8. The spring element 34 therefore biases the trigger member such thatthe contact face 20 b protrudes from the aperture 30 in the handle andthe actuating finger 20 a is spaced from the actuating switch unit 26 ofthe battery pack 10. When the trigger member 20 is in this position, themotor and fan unit 6 does not operate. Expressed another way, thetrigger arrangement takes the form of a so-called ‘dead man's trigger’which will only operate the vacuum cleaner whilst it is being depressedby a user. The coil spring element 34 preferably biases the triggermember so that the trigger has a light action. For example, for asuitable light action the coil spring element 34 should have a springconstant so that the trigger member is biased outwardly with a forceless than 8 Newtons. In the preferred embodiment, the coil spring has aspring constant which biases the trigger with a force of about 4Newtons. However, a suitable range for the spring force is between about0.5 and 5 Newtons.

In order to operate the vacuum cleaner 2, a user depresses the triggermember 20 to an operating position, which is shown in FIGS. 3 and 4. Inthis position, the activating finger 20 a of the trigger member 20engages the activating switch unit 26 of the battery pack 10 whichinitiates power supply to the electronic control module of the motor andfan unit 6 thereby operating the vacuum cleaner. Also, in this positionthe contact face 20 b of the trigger member 20 recedes into the triggeraperture 30 on the handle 8 so that it lies substantially flush with theadjoining portions of the handle 8.

The two positions of the trigger member 20 are also shown in FIGS. 5 aand 5 b from an alternative perspective. As can be seen the contact face20 a of the trigger member 20 has an outwardly curved forward portion 40bridged between two parallel walls 42 which act as a sliding guide forthe trigger member 20 against edges of the trigger aperture 30 of thehandle 8. In the non-operating position, as is shown in FIG. 5 a, thecontact face 30 of the trigger member 20 extends beyond and thereforestands proud of the adjacent surface of the handle 8. Conversely,pressing the trigger, as shown in FIG. 5 b, causes the outwardly curvedcontact face 40 to ‘merge’ with the outer profile of the handle 8. Itwill be noted that in this position the edges of the contact face liesubstantially flush with the neighbouring surfaces of the handle. Theeffect of this is to provide a particularly ergonomic user interface.During extended periods of cleaning, the requirement to depress a ‘deadman's trigger’ arrangement in order to operate the vacuum cleaner maybecome tiresome, particularly as the user's finger must adopt a slightlyextended position to maintain pressure on a trigger surface that standsproud from the grip during operation. This will affect especially thoseusers with comparatively small or weak hands and particularly thoseusers with limited mobility. In the invention, since the contact face ineffect ‘merges’ with the handle when the trigger is depressed, theuser's grip is able to adopt a more natural position in which all of thefingers are in-a-line which ensures that it is less tiring to maintainthe trigger in the operating state for an extended period of time. Itshould be noted that, although the contact face is shown as described ashaving a curved profile in the specific embodiment, a substantially flatcontact face would be a suitable alternative and would achieve the sameergonomic benefits.

As has been mentioned, the upstanding post 24 of the battery pack 10includes electrical contacts to interface with corresponding electricalconnectors in the handle 8 which, in turn, extend to an electroniccontrol module. Although the control module is not shown physically inFIGS. 1 to 4, a control system schematic of the vacuum cleaner is shownin FIG. 6 and as can be seen a control module 50 receives power andsignal inputs 52, 54 from a control circuit 56 associated with thebattery pack and also supplies a power input 58 to the motor 60, a wellas receiving a status input 62 from the motor 64. The exact nature ofthe status input from the motor is not material to the invention andwill not be described here.

In the operation described above, the control module 50 activates themotor 64 as soon as it detects power from the battery back 10 asinitiated from the triggering of the battery pack switch unit 26.However, due to the light action of the trigger member 20, there is arisk that a user may inadvertently toggle the trigger between on and offpositions rapidly for example when grasping the handle 8 and before theuser is ready to begin vacuuming. A control method to guard against thisis shown in FIG. 7.

From an initial condition 100, the routine executed by the controlmodule 50 enters a monitoring state 102 during which the status of thepower lines from the battery pack is monitored. In effect, therefore, inthis embodiment it is the voltage on the battery power connections tothe control module 50 that serves as an activation command for thecontroller. At decision gate 104, if the battery pack power signal isnegative control passes back to the monitoring step 102. If the batterypack power signal is positive, that is to say, a user has pressed thetrigger, the routine continues to step 106 which implements a delaystate before proceeding to step 108 at which point the controlleractivates the motor.

The delay step 106 introduces a predetermined delay period between theaction of the user pressing the trigger, and therefore the controlmodule 50 receiving an activation command, and the activation of themotor. Potentially the delay could be configured (during manufacture forexample) for any period of time but it is preferred if the delay is arelatively short period for example less than one second. Preferably thedelay period is between 0.2 seconds and one second and more preferablyabout 0.5 seconds. Beneficially, the delay period guards againstmomentary operation of the motor in the event that the user presses thetrigger accidentally, for example by brushing the trigger lightly whengrasping the vacuum cleaner but before being ready to being cleaning.Such a feature improves the user experience but also reduces wear on themotor by reducing the number of start/stop cycles significantly over thelifetime of the machine.

Following the activation of the motor, the process flow continues tostep 110 which checks the status of the power signal from the battery.For as long as the power signal remains positive, the process flow loopsthrough decision gate 112 back to checking step 110. However, if a userreleases the trigger, thereby causing the power signal from the batteryto go negative, the process flows through the decision gate to step 114at which the motor is deactivated. Following this, the control processreturns to monitoring the status of the power input signal while themotor is not running.

Although not mentioned above, it should be appreciated thatadditionally, or alternatively, a predetermined delay period could alsobe added between the decision step 112 and the motor deactivation step114. This would guard against the motor being turned off inadvertently,for example due to a user's finger momentarily relieving pressureslightly on the trigger. Such a deactivation delay could be implementedfor between 0.2 and 1 second, for example.

Although the trigger arrangement has been described with reference to ahandheld vacuum cleaner, it also applies to other categories of vacuumcleaners such as cylinder vacuum cleaners and upright vacuum cleaners.Referring now to FIG. 8, a cylinder vacuum cleaner 120 includes a baseunit 122 connected to a wand 124 by a flexible hose 126. The wand 124 iscarried by the hand of a user 128 at one of its ends and a cleaner head,or floor tool 130, is connected to the other end of the wand 124. Thebase unit 122 includes a cyclonic separating apparatus 132 that issupported on a rolling assembly 134 which, in this case, takes the formof upright wheels 136 mounted either side of a chassis 136. The flexiblehose 126 is mounted to the forward part of the chassis 136 and ducts airfrom the rear end of the wand 124 into the cyclonic separating apparatus132 in a known manner. The base unit 122 also includes a motor and fanunit (not shown) which is operable to draw a flow of air through thewand 124 and the separating apparatus 132. The motor and fan unit ispowered by a mains power source source via a flex or cable 138. Theskilled person will appreciate that the term ‘mains power’ is known byalternative expressions in some countries, including ‘domestic power’,‘line power’ or ‘wall power’ for example. However, the term mains poweris used here for simplicity and is intended to cover any alternatingpower source, be it 240 v/50 Hz or 120V/60 Hz for example, that isavailable from wall sockets in domestic dwellings and other buildings.

The wand 124 includes a handle assembly 140 which is shown generally inFIG. 8, but shown more clearly in FIGS. 9 to 12, and which will now bedescribed. The handle assembly 140 includes a main body portion 142 anda handgrip portion 144 that is configured so as to be graspable by auser and extends between a front tubular section 146 and a rear tubularsection 148 of the main body portion 142. The front tubular section 146is adapted to be connectable to the rear end of the wand 124 (shownghosted in FIG. 9) by means of a catch system 150 and includes a tubularair inlet 152 for receiving an air flow from the wand 124.

Between its ends, the main body portion 142 of the handle assemblysupports a cylindrical rotatable section 154 which includes an airoutlet portion 156 that extends away from the main body portion 142 atan angle from the side wall of the rotatable section 154. An outer end158 of the air outlet portion 156 is adapted for connection to the hose(not shown in FIGS. 9 to 12) and so the rotatable section 154 serves toconvey an air flow from the front end of the handle assembly 140 to thecyclonic separating apparatus 132 of the vacuum cleaner 120 via theflexible hose 126.

The handgrip portion 144 includes a trigger arrangement 160 in a similarmanner to the previous embodiment. In FIG. 9, the trigger arrangement160 is shown in a first, non-operating, position and FIG. 10 shows thehandgrip portion 144 in the same state but partially cutaway so that theinterior of the handgrip portion 144 surrounding the trigger arrangement160 can be seen. In a manner similar to the previous embodiment, thetrigger arrangement includes a trigger member 162 having an arm 164 thatis pivotably mounted inside the handgrip portion 144. At the end of thetrigger member 162 opposite the arm 164 is a contact face 166 thatextends through an aperture 168 provided in the handgrip portion 144.

The contact face 166 of the trigger member 162 stands proud of theadjacent surfaces of the handgrip portion 144 and is biased into thisposition by a switch means 170 in the form of a miniature snap-actionswitch (commonly known as a Micro-Switch™) that is located in theinterior of the handgrip portion 144 adjacent the trigger member. As canbe seen in FIG. 10, the switch 170 has a spring-like actuating arm 172which engages an abutment member 174 on the interior surface of thecontact face 166 and so the trigger is biased outwardly. Such aconfiguration ensures that the trigger member 162 has a light action,and preferably is operable with a force in the region of 0.5 N to 1.5 Nsuch that operation of such a trigger is easy for the user and avoidsfatigue. If a slightly stronger trigger operation is desired, furtherspring means may be incorporated. In this embodiment, for example, acoiled torsion spring may be incorporated at the pivot.

Electrical contacts 176 of the snap action switch are connected to acontrol board 178 by way of a lead (not shown). In the embodimentillustrated, the control board 178 also supports various other controlswitches 180 to access other functions of the vacuum cleaner—for exampleactivating and deactivating the rotatable brush bar, and modulating thesuction power of the vacuum cleaner. Further electrical leads 182, 184are provided to connect the control board 178 to the vacuum cleaner 120by way of power leads 184 configured to extend along the flexible hose,and to connect the control board 178 to the wand 124 and cleaner head130 by way of an electrical connection block 186 provided on the frontsection 146 of the handle assembly 140.

FIGS. 11 and 12 show the handle assembly 140 with the trigger member 162in an activated position. In the same manner as the first embodiment, inthis position the contact face 166 of the trigger member 162 recedesinto the trigger aperture 168 on the handle so that it liessubstantially flush with the adjoining portions of the handle. Ineffect, therefore, the contact face 166 of the trigger member 162 mergeswith the profile of the handle. It should be noted that although thehandle assembly 140 is described as being used on a cylinder vacuumcleaner, the handle assembly could also be incorporated into an uprightvacuum cleaner.

In addition to the ergonomic benefits conferred by the invention, afurther advantage of is that a cylinder or, indeed, an upright vacuumcleaner is provided with a operating switch that is not latchable in the‘on’ position as is the case for known switch mechanisms on cylinder andupright vacuum cleaners. This provides a surprising effect in that auser only activates the vacuum cleaner whilst grasping the handle ratherthan the known switch means on cylinder and upright vacuum cleaner inwhich the activating switch is required to be pressed a first time toturn the vacuum cleaner on, and then pressed a second time to turn thevacuum cleaner off. Therefore, a cylinder or upright vacuum cleanerincorporating the invention will be more energy efficient than knownvacuum cleaners which tend to be turned on at the beginning of acleaning session and left on throughout the duration of the session,whether or not the user is actually grasping the handle of the vacuumcleaner.

As an alternative to a mechanically operable switch, it should be notedthat other trigger means are viable in the context of this embodiment,for example touch sensitive switches such as light sensors, capacitivesensors or resistive sensors. Such switch arrangements are all operableto act as a ‘dead man's switch like the specific embodiment describedabove and therefore achieve the same energy efficiency advantages forcylinder and upright vacuum cleaners. It will also be appreciated thatthe control process described above with reference to FIGS. 6 and 7could also be implemented in this embodiment.

The skilled person will appreciate that variations on the aboveembodiments may be made without departing from the scope of theinvention, as defined by the claims.

For example, although the trigger member has been described above asbeing mounted at a pivot in the handle arrangement, it may also beslidably mounted.

Also, although it has been described above that the trigger memberoperates a switch mounted on the battery, it should be appreciated thatthis is only one way in which the battery pack, the trigger member andthe controller may be interfaced. Alternatively, the trigger membercould be arranged to activate a switch mounted directly, or indirectly,on the circuit board of the controller. In this case, it would be theactivation of the circuit board mounted switch that would provide thecontroller with the activation command, rather than the specificembodiment described in which the controller ‘watches’ for apredetermined voltage on the battery connections.

1. A vacuum cleaner comprising a main body and a separating apparatusassociated with the main body, wherein the main body includes a suctiongenerator for drawing air into the separating apparatus and a handlearrangement including a trigger member for activating the suctiongenerator, the trigger member being resiliently biased into a firstposition in which the suction generator does not operate, and is movableinto a second position to activate the suction generator wherein, in thefirst position, a contact surface of the trigger member is spaced awayfrom an adjacent surface of the handle arrangement and, in the secondposition, the contact face of the trigger member is substantially flushwith the adjacent surface of the handle arrangement.
 2. The vacuumcleaner of claim 1, wherein the trigger member is supported on a pivotin the interior of the handle arrangement.
 3. The vacuum cleaner ofclaim 1, wherein the trigger member is biased into the first position byway of a spring element which exerts a predetermined activation force onthe trigger member.
 4. The vacuum cleaner of claim 3, wherein the springelement is a compression spring that acts on a part of the contactsurface.
 5. The vacuum cleaner of claim 1, wherein the trigger member isbiased with a force of less than 8 N.
 6. The vacuum cleaner of claim 1,wherein the trigger member is biased with a force between 0.5 N and 6 N.7. The vacuum cleaner of claim 1, wherein the trigger member is biasedwith a force between 0.5 N and 3 N.
 8. The vacuum cleaner of claim 1,wherein the trigger member includes an actuating member that is moved bymovement of the contact face, the actuating member being arranged tocontact an activating switch of a battery pack.
 9. The vacuum cleaner ofclaim 8, wherein the battery pack is carried adjacent an end of thehandle arrangement.
 10. The vacuum cleaner of claim 9, wherein thebattery pack includes a part which extends inside the interior of thehandle, the extending part including the activating switch.
 11. Thevacuum cleaner of claim 1, comprising a controller operable to activatethe motor and fan unit in response to a command signal initiated by thetrigger member, wherein the controller implements a predetermined delayperiod between receiving an command signal and activating the suctiongenerator.
 12. A handle arrangement for a vacuum cleaner, the handlearrangement including a trigger member which is movable between firstand second positions, the trigger member being resiliently biased intothe first position in which position a contact surface of the triggermember is spaced away from an adjacent surface of the handle arrangementand wherein, in the second position, the contact face of the triggermember is substantially flush with the adjacent surface of the handlearrangement.
 13. The handle arrangement of claim 12, wherein the triggermember is supported on a pivot in the interior of the handlearrangement.
 14. The handle arrangement of claim 12, wherein the triggermember is biased into the first position by way of a resilient elementwhich exerts a predetermined activation force on the trigger member. 15.The handle arrangement of claim 14, wherein the resilient element actson a part of the contact surface.
 16. The handle arrangement of claim12, wherein the trigger member is biased with a force of less than 8 N.17. The handle arrangement of claim 12, wherein the trigger member isbiased with a force between 0.5 N and 6 N.
 18. The handle arrangement ofclaim 12, wherein the trigger member is biased with a force between 0.5N and 3 N.